Middleton crawford



(No Model.) 2 Sheets-Sheet 1.

M. CRAWFORD. SEPARATION OF METALS FROM THEIR 033s. No. 420,377. PatentedJan. 28, 1890.

[ J J [I With. as 8 es (No Model) 4 2 Sheets-Sheet 2.

. M. CRAWFORD. SEPARATION OF METALS FROM THEIR ORES.

No. 420,377. I Patented Jan. 28, 1890;

w w w Wtness e s Im/efifbar UNITED STAT S PATENT OFFICE.

MIDDLETON CRAWFORD, or LIVERPOOL, COUNTY or LANCASTER, E GLAND.

SEPARATION OF METALS FROM THEIR ORE S.

$PECIFICATION forming part of Letters Patent No. 420,377, dated January28, 1890. Application filed December 3, 1889. Serial No. 332,870. (Nomodel.) Patented in England May 27, 1889, No. 8,789.

To aZZ whom it may concern.-

Be it known that I, MIDDLETON CRAWFORD, engineer, a subject of the Queenof Great Britain, residing at 3 Oxford Street, Liverpool, in the countyof Lancaster, England, have invented certain improvements in means foreffecting the separation of particles of different specificgravities,more especially intended for the separation of gold and othermetals from crushed or divided ores, (for which I have applied for apatent in Great Britain, No. 8,7 89, dated May 27, 1889,) of which thefollowing is a specification.

My invention has for its object to provide means whereby the separationof particles of different specific gravities is effected in a veryready, complete, and efficient manner, and by the employment ofapparatus which is inex- I pensive in first cost, while it may besuccessfully and easily worked.

My said invention is more especially intended for use in the separationof gold and other metals from crushed ores containing them withoutnecessitating the amalgamating or chlorinating of the mass in the mannerhitherto employed.

I will describe my invention with reference to the accompanyingdrawings, which represent an apparatus constructed according to myinvention.

Figure 1 is a side elevation, Fig. 2 a plan, and Fig. 3 an end view, ofthe said apparatus; and Fig. 4 is a longitudinal section thereof on thelinel 2, Fig. 2. In these figures I have shown two tiers of four troughseach; but I wish it to be understood that I do not limit myself to anyparticular number of either tiers or troughs.

I take the ore or material from which the gold or other metal is to beseparated, and if it be not already in a finely-divided condition, Ireduce it to that condition in stamps or any suitable apparatus adaptedfor the purpose. I then place the divided ore or material in receptaclesA A, the bottoms of which are inclined, as shown at a, the saidreceptacles be ing in the form of troughs with sides and with ends A Aor ends only at A These troughs are placed side by side in a containerB. Thecontainers have imparted to them a sidewise movement,which canconveniently be effected by supporting the said containers byspring-hangers b b, and connecting them by rods or strips 0 c with thestraps of eccentrics d d on a shaft D, to which motion is imparted fromany convenient prime mover or by hand, so that by rotating the saidshaft the eccentrics impart a to-and-fro sidewise movement to thecontainers and the troughs which they carry. Water is supplied at theends of the troughs nearest to or toward the lower parts of theinclines. The top series of troughs have openings at a a discharginginto the lower series of troughs, which have in them discharge-openingswhich open into a passage leading to one common outlet at e. The troughsare preferably made so that they can be readily withdrawn from thecontainers for removal of the deposited matter. In order to keep thesaid containers in position, I may employ a rod or barf, enteringrecesses in the trough sides and provided with lugs f which embrace thesides, so as to keep the troughs in position both sidewise andvertically. The inclination of the troughs can be regulated by means ofthe cams g on the shafts g so that by partially rotating the shafts thecams raise or lower the ends of the troughs to alter their inclination,and to allow of this move ment the rods f are carried by arms h leditothe ends of the troughs opposite to those at which the cams aresituated, the said arms being centered at 71 to allow of the saidadjustment of the troughs.

When the crushed ore or material is placed in the troughs and the wateris admitted, the downward inclination of the bottoms of the troughs andthe passage of the water in the direction thejreverse of the incline,combined with the regulated movement of the contents of the trough bythe sidewise motion aforesaid, effect the required washing andseparation of the matters under treatment, the particles consisting ofor containing the heavier or metallic portions descending and passingback toward the lower ends of the inclined surfaces,wh.ich lower endsconstitute wells or receivers for the said portions, from which thedeposit can be emptied, either by removing the troughs or by tippingthem up, or by causing the bottoms of the troughs to move forward towardthe outlet ends of the said trough.

My improved troughs may be used singly or in any suitable number,preferably placed side by side and either in one plane orin two or moreplanes or tiers, the series above discharging into the series beneath,and the troughs may have one or more inclines at bottom.

I have found that in order to obtain the best results certainproportions are requisite, and that the best effect is obtained if thetroughs have imparted to them a sidewise movement of about one-third ofthe Width of the troughs. About six inches is a Very convenient widthfor the troughs, and their sides should be of or about the same height.The inclines at the bottom of the troughs are preferably about one intwelve, and the length of each incline is preferably about twelveinches; but some variation is permissible in the dimensions. Forinstance, although the best effects are obtained by the aforesaid dimensions, good effects are obtainable if the trough be as low as threeor as high as nine inches in depth and width, and the inclines may varyfrom one in twelve to one in fortyeight or three in sixteen, and thelength of the inclines may be as low as four or six inches,- or they maybe longer than twelve inches up to, say, about twenty-four inches. Thesidewise movement of the troughs should not vary in extent beyondone-quarter inch greater or less than a third of the width of thetroughs, although results superior to those hitherto obtained may beattained if the said sidewise movement be as low as one-twelfth or ashigh as two-thirds the width of the trough.

hen the machine is at work, the agitation effected by the sidewisemovement of the troughs causes a thorough washing and separation of therefuse from the particles which are to be retained, which latter, owingto the inclination of the bottoms of the troughs, settle in the pocketsformed by the lower ends of the inclines. Moreover, the sides of thetroughs cause the water to splash back over the surface of the contentsof the troughs, so causing the carrying down of any floating particleswhich it is desired to recover, but which would otherwise pass off withthe water. In order to facilitate the precipitation of the particles, Ifind it advantageous to use a dipping-board or baflie, as at i in thedrawings, Fig. 4, which enters the water, but leaves a space betweenitself and the bottom of the trough. In cases where it is difiicult orimpracticable to obtain a supply of water for working my arrangement oftroughs they may be used without water.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is- 1. In a machine or apparatus for separating materialsof diiferentspecific :gravities, the combination of a fixed frame and amovable trough or troughs having an incline or inclines at the bottom,with devices, substantially as described, for imparting a reciprocatingsidcwise movement to the trough or troughs to an extent of aboutone-third of: the width of such trough, substantially as described.

2. In an apparatus for separating materials of different specificgravities, the combination of a trough or troughs having an incline orinclines at the bottom, with a Water-supply at that end of the trough ortroughs having the downward end of the incline, and a discharge for thewater at the opposite end of the trough or troughs, and devices,substantially as described, for impartinga sidewise reciprocatingmovement to the said trough or troughs, all substantially as set forth.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

MIDDLETON CRAWFORD.

\Vitnesses:

EDWD. GEO. DAVIES, WILLIAM F. UPTON, Both 0f4=7 Lincolns Inn Fields,London, VV. 0.

